Meta tags are extremely important aspect of your website (especially the meta description) here's what they are:
HTML lets authors specify meta data -- information about a document rather than document content -- in a variety of ways.
For example, to specify the author of a document, one may use the META element as follows:
<META name="Author" content="Dave Raggett">
The META element specifies a property (here "Author") and assigns a value to it (here "Dave Raggett").
This specification does not define a set of legal meta data properties. The meaning of a property and the set of legal values for that property should be defined in a reference lexicon called a profile. For example, a profile designed to help search engines index documents might define properties such as "author", "copyright", "keywords", etc.
Specifying meta data
In general, specifying meta data involves two steps:
1 Declaring a property and a value for that property. This may be done in two ways:
From within a document, via the META element.
From outside a document, by linking to meta data via the LINK element (see the section on link types).
2 Referring to a profile where the property and its legal values are defined. To designate a profile, use the profile attribute of the HEAD element.
You can also watch our explanation of how to create proper meta tags for seo